vec2par {lmomco} | R Documentation

## Convert a Vector of Parameters to a Parameter Object of a Distribution

### Description

This function converts a vector of parameters to a parameter object of a distribution. The type of distribution is specified in the argument list: `cau`, `exp`, `gam`, `gev`, `glo`, `gno`, `gpa`, `gum`, `kap`, `nor`, `pe3`, `revgum`, `wak`, and `wei`.

### Usage

    vec2par(vec, type, nowarn=FALSE, ...)

### Arguments

`vec` | A vector of parameter values for the distribution specified by type.
`type` | Three character distribution type (for example, `type='gev'`).
`nowarn` | A logical switch on warning surpression. If `TRUE` then `options(warn=-1)` is made and restored on return. This switch is to permit calls in which warnings are not desired as the user knows how to handle the returned value—say in an optimization algorithm.
`...` | Additional arguments for the `are.par.valid` call that is made internally.

### Details

If the distribution is a Reverse Gumbel (`type=revgum`)) or Generalized Pareto (`type=gpa`) , which are two-parameter or three-parameter distributions, the third or fourth value in the vector is the zeta of the distribution. zeta represents the fraction of the sample that is noncensored, or number of observed (noncensored) values divided by the sample size. The zeta represents censoring on the right, that is there are unknown observations above a threshold or the largest observed sample. Consultation of `parrevgum` or `pargpaRC` should elucidate the censoring discussion.

### Value

An R `list` is returned. This list should contain at least the following items, but some distributions such as the `revgum` have extra.

`type` | The type of distribution in three character format.
`para` | The parameters of the distribution.
`source` | Attribute specifying source of the parameters—“vec2par”.

### Author(s)

W.H. Asquith

### See Also

`lmom2par`

### Examples

    para <- vec2par(c(12,123,0.5),'gev')
    Q <- quagev(0.5,para)

[Package lmomco version 0.92 Index]